1,703 research outputs found
Preliminary Phytochemical and Physicochemical Characterization of Gynura segetum (Lour) Merr (Compositae) Leaf
Purpose: To carry out phytochemical and physicochemical studies on the leaves of Gynura segetum.Methods: Preliminary phytochemical and physicochemical studies using chromatographic techniques,were carried out, Parameters evaluated include ash value, loss on drying and extractive value, amongst others. .Results: Phytochemical results revealed that the leaves of Gynura segetum contain alkaloid, terpene, flavonoid, tannin and saponin. Mean ash value (%) was 13.5 (total), 2.49 (acid-insoluble ash) and 6.14 (water-soluble ash). Loss on drying was 10.70 % while extractive value was 20.60 % in water and 14.13 % in ethanol. Thin layer chromatography (TLC) analysis indicates the presence of rutin in the methanol extract of G. segetum and this was supported by high performance liquid chromatography (HPLC) studies.Conclusion: Useful quantitative and descriptive data essential for identifying and characterizing the plant for the purpose of quality control are presented.Keywords: Gynura segetum, Quality control, Extractive, Ash valu
A study of primary dental enamel from preterm and full-term children using light and scanning electron microscopy
Purpose: The aim of this study was to examine the enamel thickness of the maxillary primary incisors of preterm children with very low birth weight (< 1,500 g) compared to full-term children with normal birth weight. Methods: A total of 90 exfoliated maxillary primary central incisors were investigated using light microscopy and scanning electron microscopy (SEM). Three serial buccolingual ground sections of each tooth were examined under light microscopy, and maximum dimensions of the prenatally and postnatally formed enamel were measured. Results: The enamel of preterm teeth was approximately 20% thinner than that for fullterm teeth. Most of the reduction was observed in the prenatally formed enamel. This was 5 to 13 times thinner than that for full-term children (P < .001). The catch-up thickness of postnatally formed enamel did not compensate fully for the decrease in prenatal enamel (P < .001). Although none of the teeth used in this study had enamel defects visible to the naked eye, 52% of preterm teeth showed enamel hypoplasia under SEM, compared with only 16% found on full-term teeth (P < .001). These defects were present as pits or irregular, shallow areas of missing enamel. Conclusions: Preterm primary dental enamel is abnormal in surface quality, and is significantly thinner compared to full-term enamel. The thinner enamel is due mainly to reduced prenatal growth and results in smaller dimensions of the primary dentition
What makes brands achieve iconic status?
We propose that brands do not achieve iconic status by chance. This article focuses on how brands manage iconic status effectively. Drawing on an exploratory study of iconic brands, we identify a brand's ability to inspire consumers and connect with them on a personal level as well as its visual identity and presence in consumers' mind as critical elements of brand status. Consumers' perceptions of a sample of brands were investigated through in-depth interviews, followed by the examination of these brands' activities through case-study analyses. The alignment between brand strategies and the relevant features highlighted by consumers was then assessed. A comprehensive framework for achieving iconicity is presented and discussed.Working Pape
Nox1 oxidase suppresses influenza a virus-induced lung inflammation and oxidative stress
Influenza A virus infection is an ongoing clinical problem and thus, there is an urgent need to understand the mechanisms that regulate the lung inflammation in order to unravel novel generic pharmacological strategies. Evidence indicates that the Nox2-containing NADPH oxidase enzyme promotes influenza A virus-induced lung oxidative stress, inflammation and dysfunction via ROS generation. In addition, lung epithelial and endothelial cells express the Nox1 isoform of NADPH oxidase, placing this enzyme at key sites to regulate influenza A virus-induced lung inflammation. The aim of this study was to investigate whether Nox1 oxidase regulates the inflammatory response and the oxidative stress to influenza infection in vivo in mice. Male WT and Nox1-deficient (Nox1−/y) mice were infected with the moderately pathogenic HkX-31 (H3N2, 1×104 PFU) influenza A virus for analysis of bodyweight, airways inflammation, oxidative stress, viral titre, lung histopathology, and cytokine/chemokine expression at 3 and 7 days post infection. HkX-31 virus infection of Nox1−/y mice resulted in significantly greater: loss of bodyweight (Day 3); BALF neutrophilia, peri-bronchial, peri-vascular and alveolar inflammation; Nox2-dependent inflammatory cell ROS production and peri-bronchial, epithelial and endothelial oxidative stress. The expression of pro-inflammatory cytokines including CCL2, CCL3, CXCL2, IL-1β, IL-6, GM-CSF and TNF-α was higher in Nox1−/y lungs compared to WT mice at Day 3, however, the expression of CCL2, CCL3, CXCL2, IFN-γ and the anti-inflammatory cytokine IL-10 were lower in lungs of Nox1−/y mice vs. WT mice at Day 7. Lung viral titre, and airways infiltration of active CD8+ and CD4+ T lymphocytes, and of Tregs were similar between WT and Nox1−/y mice. In conclusion, Nox1 oxidase suppresses influenza A virus induced lung inflammation and oxidative stress in mice particularly at the early phases of the infection. Nox1 and Nox2 oxidases appear to have opposing roles in the regulation of inflammation caused by influenza A viruses
Benefits for public healthcare buildings towards Net Zero Energy Buildings (NZEBs): initial reviews
NZEBs concept has received incrementing attention especially since European
Union Parliament are progressively moving towards regulation in which all new buildings to
be “nearly Zero-Energy” Buildings by 2020. Even though this concept delivers promising
benefits, previous studies found that the benefit of NZEB is still in vague to the Malaysian
construction industry, mostly for healthcare buildings. The NZEBs concept implementation is
critical in healthcare building as it seen as a key part of the needed transition towards
sustainable development. This paper aims to define benefits of NZEBs practices through initial
investigation among architects. Several existing energies works of literature and pilot studies
by using semi-structured interviews were conducted. The findings divulge that, although the
term ‘NZEBs design strategies’ is not being used largely across construction industry in
Malaysia, some sustainable practices related to the design stage of construction has been
implemented. The findings are also promising in growing awareness, practices and
implementation of NZEBs design strategies by the practitioner in Malaysia. It is foreseen that
the paper will provide a straightforward knowledge for future research in NZEBs design
strategies practices for healthcare buildings construction in Malaysia
Model-based planning deficits in compulsivity are linked to faulty neural representations of task structure
Compulsive individuals have deficits in model-based planning, but the mechanisms that drive this have not been established. We examined two candidates—that compulsivity is linked to (i) an impaired model of the task environment and/or (ii) an inability to engage cognitive control when making choices. To test this, 192 participants performed a two-step reinforcement learning task with concurrent EEG recordings and we related the neural and behavioral data to their scores on a self-reported transdiagnostic dimension of compulsivity. To examine subjects’ internal model of the task, we used established behavioral and neural responses to unexpected events (reaction time (RT) slowing, P300 and parietal-occipital alpha-band power) measured when an unexpected transition occurred. To assess cognitive control, we probed theta power at the time of initial choice. As expected, model-based planning was linked to greater behavioral (RT) and neural (alpha power, but not P300) sensitivity to rare transitions. Critically, the sensitivity of both RT and alpha to task structure was weaker in those high in compulsivity. This RT-compulsivity effect was tested and replicated in an independent pre-existing dataset (N = 1413). We also found that mid-frontal theta power at the time of choice was reduced in high compulsive individuals though its relation to model-based planning was less pronounced. These data suggest that model-based planning deficits in compulsive individuals may arise, at least in part, from having an impaired representation of the environment, specifically how actions lead to future states
A Longitudinal Study of Streptococcus mutans Colonization in Infants after Tooth Eruption
We previously reported that, before tooth eruption, over one-half of infants aged 6 mos were already infected with Streptococcus mutans. The aim of this investigation was to determine the colonization of S. mutans after tooth eruption in the same cohort of 111 infants (35 pre-term, 76 full-term). Our results showed that S. mutans colonization increased with increasing age, so that by 24 mos of age, 84% harbored the bacteria (p 10(5) CFU/mL (p < 0.02). In contrast, non-colonization of S. mutans was associated with toothbrushing (p < 0.03) and multiple courses of antibiotics (p < 0.001). Analysis of our data establishes the timing of S. mutans colonization in children from birth to 24 mos of age
Longitudinal Current Dissipation in Bose-glass Superconductors
A scaling theory of vortex motion in Bose glass superconductors with currents
parallel to the common direction of the magnetic field and columnar defects is
presented. Above the Bose-glass transition the longitudinal DC resistivity
vanishes much faster than the
corresponding transverse resistivity , thus {\it reversing} the usual anisotropy of electrical transport in
the normal state of layered superconductors. In the presence of a current at an angle with the common field and columnar defect axis, the
electric field angle approaches as .
Scaling also predicts the behavior of penetration depths for the AC currents as
, and implies a {\it jump discontinuity} at in
the superfluid density describing transport parallel to the columns.Comment: 5 pages, revte
Genetic regulation of glucoraphanin accumulation in Beneforté® broccoli
Diets rich in broccoli (Brassica oleracea var italica) have been associated with maintenance of cardiovascular health and reduction in risk of cancer. These health benefits have been
attributed to glucoraphanin that specifically accumulates in broccoli. The development of broccoli with enhanced concentrations of glucoraphanin may deliver greater health benefits.
Three high-glucoraphanin F1 broccoli hybrids were developed in independent programmes through genome introgression from the wild species Brassica villosa. Glucoraphanin and other metabolites were quantified in experimental field trials. Global SNP analyses quantified the differential extent of B. villosa introgression
The high-glucoraphanin broccoli hybrids contained 2.5–3 times the glucoraphanin content of standard hybrids due to enhanced sulphate assimilation and modifications in sulphur partitioning between sulphur-containing metabolites. All of the high-glucoraphanin hybrids possessed an introgressed B. villosa segment which contained a B. villosa Myb28 allele. Myb28
expression was increased in all of the high-glucoraphanin hybrids. Two high-glucoraphanin hybrids have been commercialised as Beneforte broccoli.
The study illustrates the translation of research on glucosinolate genetics from Arabidopsis to broccoli, the use of wild Brassica species to develop cultivars with potential consumer benefits, and the development of cultivars with contrasting concentrations of glucoraphanin for use in blinded human intervention studie
Detailed deletion mapping at chromosome 11q23 in colorectal carcinoma
Loss of heterozygosity (LOH) is frequent at the chromosomal region 11q22–q23 in several types of tumours of diverse cell origin. Previous investigations of LOH at this chromosomal region in colorectal carcinoma have been contradictory in their findings, and have only included between 1–4 loci. In order to define any regions of LOH on 11q23, we investigated 16 loci between D11S940 and D11S934 on the long arm of chromosome 11 using microsatellite analysis. Of 57 colorectal carcinomas specimens, 36 (63.2%) demonstrated LOH at one or more marker, with the highest frequencies of LOH at D11S1340 (41.0%), located between 105.13–111.97 Mb from the centromere, and D11S924 (37.1%) and D11S4107 (40.5%), both located approximately 113 Mb from the centromere. No statistically significant associations between LOH and age-of-presentation or Dukes’ stage were found. LOH was observed in colorectal tumours of all Dukes’ stages, including Dukes’ stages A and B, suggesting that the inactivation of a tumour suppressor gene(s) on 11q23 occurs in the early stages of colorectal carcinoma. These results confirm the presence of putative tumour suppressor gene(s) at chromosome 11q23, involved in the carcinogenesis of colorectal carcinoma, and will facilitate future identification of candidate genes. © 2000 Cancer Research Campaig
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